Aspects of the present disclosure relate generally to wireless communication systems, and more particularly, to transmitting/receiving beams and/or recovering from beam failure.
Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems, and single-carrier frequency division multiple access (SC-FDMA) systems.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. For example, a fifth generation (5G) wireless communications technology (which can be referred to as 5G new radio (5G NR)) is envisaged to expand and support diverse usage scenarios and applications with respect to current mobile network generations. In an aspect, 5G communications technology can include: enhanced mobile broadband addressing human-centric use cases for access to multimedia content, services and data; ultra-reliable-low latency communications (URLLC) with certain specifications for latency and reliability; and massive machine type communications, which can allow a very large number of connected devices and transmission of a relatively low volume of non-delay-sensitive information. As the demand for mobile broadband access continues to increase, however, further improvements in 5G communications technology and beyond may be desired.
In some wireless communication technologies, such as 5G, beamformed signals (also referred to as “beams”) can be transmitted by a transmitting node for receipt by a receiving node. The receiving node can select a received beam that is determined to be desirable (e.g., that exhibits higher received strength or quality than one or more of the other beams) and can notify the transmitting node of the selection. The transmitting node, in turn, can beamform, based on the selected beam, subsequent signals for receipt by the receiving node. In addition, based on a reciprocal theory, the receiving node can similarly beamform signals to transmit to the transmitting node using the same (or reversed) beam. Specifically, in gNB to user equipment (UE) communications, the same downlink beam (transmitted from gNB to UE) and uplink beam (transmitted from UE to gNB) can be used.